The dual-serial port WAN Interface Card (WIC-2A/S) provides higher
levels of serial port density for a single WIC and is supported on the Cisco
1700, 2600, and 3600 series. The low serial speed WIC-2A/S supports up to 128
Kbps synchronous or 115.2 Kbps asynchronous serial links. Each port on a WIC is
a different physical interface and can support different protocols such as
Point-to-Point Protocol (PPP) or Frame Relay and Data Terminal Equipment/Data
Communications Equipment (DTE/DCE). This WIC supports mixed asynchronous and
synchronous operation on a single card as well.

These dual-serial port WICs feature Cisco's new, compact, Smart Serial
connectors to support a wide variety of electrical interfaces when used with
the appropriate transition cable. This includes: V.35, RS-232, RS-449, RS-530,
RS-530A in male and female versions for both DTE and DCE devices. This feature
provides easy configuration and reconfiguration as network requirements change,
without the need of purchasing a different serial interface card.

The information in this document was created from the devices in a
specific lab environment. All of the devices used in this document started with
a cleared (default) configuration. If your network is live, make sure that you
understand the potential impact of any command.

The default setting for this module is synchronous. Issue the
physical-layer
async command in order to configure the module for
asynchronous communication. Here is a section of an asynchronous
configuration:

Issue the physical-layer sync command or the
no physical-layer async command in order to revert
to the default sync mode. Refer to
Configuring
Serial Interfaces for more information on how to configure the interface
for normal serial operation.